[PATCH 2 of 2 v2 sparse-ext maybe-for-stable] sparse: treat paths as cwd-relative

[Kostia Balytskyi]

# HG changeset patch
# User Kostia Balytskyi <ikostia at fb.com>
# Date 1501360312 25200
#      Sat Jul 29 13:31:52 2017 -0700
# Branch stable
# Node ID d596185be467a35f5d915d63f94c3fead982c1c5
# Parent  c9a99abd647235c4dfd167ffcb9fccd66f0e0e4b
sparse: treat paths as cwd-relative

This commit makes it so sparse treats passed paths as CWD-relative,
not repo-root-realive. This is a more intuitive behavior in my (and some
other FB people's) opinion.

This is breaking change however. My hope here is that since sparse is
experimental, it's ok to introduce BCs. That is also the reason why I am
sending this during a freeze: the experimental status of the feature probably
means that these two patches can just land on stable.

The reason (glob)s are needed in the test is this: in these two cases we
do not supply path together with slashes, but `os.path.join` adds them, which
means that under Windows they can be backslashes. To demonstrate this behavior,
one could remove the (glob)s and run `./run-tests.py test-sparse.t` from
MinGW's terminal on Windows.

diff --git a/hgext/sparse.py b/hgext/sparse.py
--- a/hgext/sparse.py
+++ b/hgext/sparse.py
@@ -155,7 +155,8 @@ def _clonesparsecmd(orig, ui, repo, *arg
     if include or exclude or enableprofile:
         def clonesparse(orig, self, node, overwrite, *args, **kwargs):
             sparse.updateconfig(self.unfiltered(), pat, {}, include=include,
-                                exclude=exclude, enableprofile=enableprofile)
+                                exclude=exclude, enableprofile=enableprofile,
+                                usereporootpaths=True)
             return orig(self, node, overwrite, *args, **kwargs)
         extensions.wrapfunction(hg, 'updaterepo', clonesparse)
     return orig(ui, repo, *args, **opts)
diff --git a/mercurial/sparse.py b/mercurial/sparse.py
--- a/mercurial/sparse.py
+++ b/mercurial/sparse.py
@@ -616,7 +616,7 @@ def importfromfiles(repo, opts, paths, f
 
 def updateconfig(repo, pats, opts, include=False, exclude=False, reset=False,
                  delete=False, enableprofile=False, disableprofile=False,
-                 force=False):
+                 force=False, usereporootpaths=False):
     """Perform a sparse config update.
 
     Only one of the actions may be performed.
@@ -639,6 +639,11 @@ def updateconfig(repo, pats, opts, inclu
         if any(os.path.isabs(pat) for pat in pats):
             raise error.Abort(_('paths cannot be absolute'))
 
+        if not usereporootpaths:
+            # let's treat paths as relative to cwd
+            cwd = repo.getcwd()
+            pats = [os.path.join(cwd, pat) for pat in pats]
+
         if include:
             newinclude.update(pats)
         elif exclude:
diff --git a/tests/test-sparse.t b/tests/test-sparse.t
--- a/tests/test-sparse.t
+++ b/tests/test-sparse.t
@@ -48,6 +48,27 @@ TODO: See if this can be made to fail th
   [255]
 #endif
 
+Paths should be treated as cwd-relative, not repo-root-relative
+  $ mkdir subdir && cd subdir
+  $ hg debugsparse --include path
+  $ hg debugsparse
+  [include]
+  $TESTTMP/myrepo/hide
+  hide
+  subdir/path (glob)
+  
+  $ cd ..
+  $ echo hello > subdir/file2.ext
+  $ hg debugsparse --include subdir/*.ext  # let us test globs
+  $ hg debugsparse
+  [include]
+  $TESTTMP/myrepo/hide
+  hide
+  subdir/file2.ext
+  subdir/path (glob)
+  
+  $ rm -rf subdir
+
 Verify commiting while sparse includes other files
 
   $ echo z > hide